Archive
05/17/2018 – Ephemeris – Venus and the Moon tonight and viewing Venus in the daytime
Ephemeris for Thursday, May 17th. Today the Sun will be up for 14 hours and 54 minutes, setting at 9:06, and it will rise tomorrow at 6:11. The Moon, 2 days past new, will set at 11:40 this evening.
This afternoon at 2:11 the Moon will appear to pass Venus. This will be impossible to see since the Moon is going to be much dimmer than Venus. Venus can indeed be seen in the daylight. I’ve seen it many times with binoculars or a telescope, but only once with the naked eye. The latter time was not long before sunset. It is essential that to spot Venus in the daytime by any of these means that one is in the shade, by putting the Sun behind a building, and knowing where Venus is supposed to be using a program on a smart phone. By tonight the Moon will have moved eastward past Venus by up to 13 of its diameters and will also be displaying earthshine, the reflection of the Earth off its night side.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus and the Moon at 10 p.m. May 17, 2018. Created using Stellarium.
05/16/2018 – Ephemeris – Let’s check out the whereabouts of the bright planets
Ephemeris for Wednesday, May 16th. Today the Sun will be up for 14 hours and 52 minutes, setting at 9:05, and it will rise tomorrow at 6:12. The Moon, 1 day past new, will set at 10:32 this evening.
It’s Wednesday again and time to look for the bright planets. Two of them are in the evening sky. The brilliant beacon of Venus will be visible in the western twilight from about 9:25 p.m. until it sets at 11:44. Jupiter will be low in the southeast as it gets dark. Jupiter is only out shown by Venus and the Moon. And after Venus sets will have the night to itself as the brightest star-like object. Binoculars will show it to be not quite star-like in size, that is it will appear as a tiny orb. It will be accompanied by several satellites which will shift positions night to night. Saturn will rise at 12:12 a.m. in the east-southeast. Mars will rise at 1:46 a.m. and is now outshining Saturn, and will, this summer even outshine Jupiter.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Venus at 10 p.m. May `6, 2018. Click on image to enlarge. Created using Stellarium.
Jupiter and its moons at 10:30. May 16, 2018. Created using Cartes du Ciel (Sky Charts).
Morning planets at 5:30 a.m. May 17, 2017. Created using Stellarium.
Telescopic Saturn and Mars with the same magnification at 5:30 a.m. May 17, 2018. Inset shows Mars at higher magnification. Created using Cartes du Ciel (Sky Charts).
Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on May 16, 2018. The night ends on the left with sunrise on the 17th. Click on the image to enlarge. Created using my LookingUp program.
5/15/2018 – Ephemeris – Two thirds thru spring
Ephemeris for Tuesday, May 15th. Today the Sun will be up for 14 hours and 49 minutes, setting at 9:04, and it will rise tomorrow at 6:13. The Moon is new today, and won’t be visible.
Here we are at the middle of May, nearly two-thirds through spring and in the west only a few winter stars remain. Castor and Pollux of Gemini are horizontal in the west, Procyon the Little Dog Star is below and left of them, Capella in Auriga is in the northwest, but for most of the IPR listening area it will never quite set. At 10:30 Betelgeuse in Orion the hunter will be setting, chased from the skies by Scorpius the scorpion, which is rising in the southeast. In one story it is the sting of this scorpion that killed him. Already at that time two-thirds of the stars of the summer Triangle are up. Bright Vega in Lyra the harp, and Deneb in Cygnus the swan. The Big Dipper reigns overhead as spring is in full bloom.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The sky dome for 10:30 p.m. May 15, 2018 showing the stars and constellations. It may not work for any latitude or time, but it works for our location, near 45 degrees north. Created using Stellarium.
05/14/2018 – Ephemeris – Big Dipper: Pointer to the Stars
Ephemeris for Monday, May 14th. Today the Sun will be up for 14 hours and 47 minutes, setting at 9:03, and it will rise tomorrow at 6:14. The Moon, 1 day before new, will rise at 6:45 tomorrow morning.
The Big Dipper points to other stars and constellations. Right now the Big Dipper is nearly overhead. The front bowl stars point to Polaris, the North Star which never seems to move in the sky. The handle can be used to find two stars. First follow the arc of the handle away from the bowl to find the fourth brightest night-time star Arcturus in the base of the kite shaped constellation of Boötes. Straighten the arc to a spike and continue to the south and you will come to the bright blue-white star Spica in Virgo the virgin. You can remember these stars with the phrase “Follow the arc of the handle to Arcturus and then spike to Spica” or if you prefer the alternate pronunciation of the latter star “Speak to Speeka”.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
As can be seen below, there was one pointer function that didn’t make it into the program: A leaky dipper drips on Leo.
Using the Big Dipper as a pointer to other stars. The pointers to Polaris could be life saving, since it is always north. The view is southward. The cross displayed near the center is the zenith. One might want to lay down to take all this in. Created using my LookingUp program.
05/11/2018 – Ephemeris – Corvus, Crater, Hydra and a fig
Ephemeris for Friday, May 11th. The Sun rises at 6:19. It’ll be up for 14 hours and 40 minutes, setting at 8:59. The Moon, half way from last quarter to new, will rise at 5:09 tomorrow morning.
The small constellation of Corvus the crow is located low in the south at 10:30 this evening. It’s made of 5 dim stars, but the pattern is a distinctive distorted box with two stars at the upper left marking that corner. To the right is a fainter constellation of a thick stemmed goblet called Crater. Both appear above the long constellation of Hydra the water snake who is slithering above the southern horizon. In Greek mythology Corvus, then white, was the god Apollo’s pet. He once bid Corvus to take a cup and fetch him some water. Corvus however dallied and waited for a green fig to ripen. Corvus then grabbed a snake and returned with a story on how the snake had delayed him. The angry Apollo turned the crow and all crows black to this day.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Corvus, Crater and Hydra finder chart for 10:30 p.m. May 11, 2017. Apollo is not in the night sky, and is presumably resting after guiding the Sun’s (Helios) chariot across the daytime sky. The fig? Corvus ate it. Click on the image to enlarge. Created using Stellarium and GIMP.
05/10/2018 – Ephemeris – Berenice’s Hair
Ephemeris for Thursday, May 10th. The Sun rises at 6:20. It’ll be up for 14 hours and 38 minutes, setting at 8:58. The Moon, 3 days past last quarter, will rise at 4:42 tomorrow morning.
High in the southeast at 10 p.m. is a tiny and faint constellation of Coma Berenices, or Berenice’s hair. In it are lots of faint stars arrayed to look like several strands of hair. The whole group will fit in the field of a pair of binoculars, which will also show many more stars. The hank of hair was supposed to belong to Berenice, Queen of Egypt, of the 3rd century BCE. Coma Berenices is the second closest star cluster to us at only 250 light years away, after the Hyades, the face of Taurus the bull now setting in the west. It’s in an odd spot for a galactic star cluster, that’s supposed to lie in the plane of the Milky Way. It actually lies at the galactic pole. That’s an illusion because it’s so close to us. It’s still really in the plane of the Milky Way.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Coma Berenices finder chart for 10 p.m. May 10, 2018. Created using Stellarium.
Coma Berenices as it might look in a pair of binoculars. Telescopes are too powerful. Created using Stellarium.
05/09/2018 – Ephemeris – We’ve got two evening planets now
Ephemeris for Wednesday, May 9th. The Sun rises at 6:21. It’ll be up for 14 hours and 35 minutes, setting at 8:57. The Moon, 2 days past last quarter, will rise at 4:14 tomorrow morning.
It’s Wednesday again and time to look for the bright planets. Tada! We now have a second planet in the evening sky. More on that in a moment. Venus will be visible low in the western twilight from about 9:15 p.m. until it sets at 11:29. Jupiter is up before sunset in the southeast. Which makes it an evening planet. It is at its closest and its brightest at magnitude -2.5. Venus is at magnitude -3.9. Magnitudes are like golf scores, the lower the magnitude the brighter the object. Saturn will rise at 12:49 a.m., while Mars will rise at 2:05 a.m. At 5:30 tomorrow morning these three planets will be strung across the southern sky. Bright Jupiter will be in the southwest, dimmer Mars and Saturn will be in the south, with Mars to the left of Saturn.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Sorry, no graphics this time. I’m still fighting the flu bug. It’s not a cold as I reported with Monday’s post but a full blown case of the flu.
05/08/2018 – Ephemeris – Jupiter at opposition
Ephemeris for Tuesday, May 8th. The Sun rises at 6:23. It’ll be up for 14 hours and 33 minutes, setting at 8:56. The Moon, 1 day past last quarter, will rise at 3:45 tomorrow morning.
At 8:10 p.m. Jupiter will be in opposition, that is opposite the Sun in the sky. Thursday at 8 a.m. it will be its closest to the Earth at 408.9 million miles away, and its biggest in telescopes at 44.8 arc seconds. The Moon averages about 1,800 arc seconds in diameter. So the Moon appears 40 times larger in diameter, meaning you could put 40 Jupiters across the diameter of the moon. Jupiter’s disk is visible in binoculars, along with several of its moons. The moons change position from night to night. Most computer planetarium programs will show the moons for any time past and future. Telescopes will reveal that Jupiter’s face is crossed by bands of contrasting colors of clouds, and the famous Great Red Spot.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter with its Great Red Spot November 18, 2012 by Scott Anttila.
05/07/2018 – Ephemeris – Twilight
Note: Sorry for the delay. I was hit with a fast developing cold Sunday. So I was unable to post this at my normal time, and was unable to record my next Tuesday through Monday programs.
Ephemeris for Monday, May 7th. The Sun rises at 6:24. It’ll be up for 14 hours and 30 minutes, setting at 8:55. The Moon, at last quarter today, will rise at 3:14 tomorrow morning.
We are in the time of year when it appears that twilight doesn’t seem to end. There are three definitions of twilight, Civil, Nautical and Astronomical. Each ends in the evening when the Sun is 6, 12, and 18 degrees below the horizon respectively. Astronomers don’t really care about civil twilight, the sky is too bright. Sailors using a sextant for star positions can usually see the horizon for star sighting up to the end of nautical twilight. Astronomers consider the skies dark at the end of astronomical twilight, barring he Moon being up. The brightest stars and planets become visible a half hour after sunset. We begin to pick out constellations at the end of nautical twilight. For instance, for tonight, nautical twilight ends at 10:10 p.m., while astronomical twilight ends at 10:57.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
05/04/2018 – Ephemeris – Tonight I present Venus from the mists of time to today
Ephemeris for Friday, May 4th. The Sun rises at 6:28. It’ll be up for 14 hours and 23 minutes, setting at 8:51. The Moon, 3 days before last quarter, will rise at 1:15 tomorrow morning.
The planet Venus is our evening star now. I’ve been talking about it on this program lately. Want to hear and see more? Tonight at 8 p.m. at the May meeting of the Grand Traverse Astronomical Society at Northwestern Michigan College’s Rogers Observatory, I will be giving an illustrated talk: Venus from the mists of time to today. To the early Greeks it was two planets. To the Maya it was a calendar. In the 18th century it was a way to measure the size of the solar system. Today, it could be what our future looks like. After the meeting, at 9 p.m. the society will host a star party to view the planets Venus and Jupiter. The observatory is located south of Traverse City on Birmley Road between Garfield and Keystone roads.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
5 Pages of the Dresden Codex produced by the Maya tracking Venus’ appearances in the skies over the Yucatan. for 104 years. The Dresden Codex is one of only 4 surviving Mayan Codices.
Bob Moler's Ephemeris Blog 